Wednesday, April 17, 2013

Dental anesthesia may interrupt development of wisdom teeth in children

Researchers from Tufts University School of Dental Medicine have
discovered a statistical association between the injection of local
dental anesthesia given to children ages two to six and evidence of
missing lower wisdom teeth. The results of this epidemiological study,
published in the April issue of The Journal of the American Dental
Association, suggest that injecting anesthesia into the gums of young
children may interrupt the development of the lower wisdom tooth.

"It is intriguing to think that something as routine as local anesthesia
could stop wisdom teeth from developing. This is the first study in
humans showing an association between a routinely- administered,
minimally-invasive clinical procedure and arrested third molar growth,"
said corresponding author, Anthony R. Silvestri, D.M.D., clinical
professor in the department of prosthodontics and operative dentistry at
Tufts University School of Dental Medicine.

Wisdom teeth are potentially vulnerable to injury because their
development – unlike all other teeth – does not begin until well after
birth. Between two and six years of age, wisdom tooth (third molar) buds
begin to develop in the back four corners of the mouth, and typically
emerge in the late teens or early adulthood. Not everyone develops
wisdom teeth, but for those who do, the teeth often become impacted or
problematic.

The American Association of Oral and Maxillofacial Surgeons reports that
nine out of 10 people will have at least one impacted wisdom tooth,
which can cause bad breath, pain, and/or infection. For this reason,
many dentists recommend surgery to remove wisdom teeth to prevent
disease or infection.

A developing wisdom tooth, called a bud, is vulnerable to injury for a
relatively long time because it is tiny, not covered by bone, and only
covered by a thin layer of soft tissue. When a tooth bud first forms, it
is no bigger than the diameter of the dental needle itself. The soft
tissue surrounding the budding tooth is close to where a needle
penetrates when routine dental anesthesia is injected in the lower jaw,
for example when treating cavities.

Using the Tufts digital dental record system, the researchers identified
records of patients who had received treatment in the Tufts pediatric
dental clinic between the ages of two and six and who also had a dental
x-ray taken three or more years after initial treatment in the clinic.
They eliminated records with confounding factors, such as delayed dental
development, and analyzed a total of 439 sites where wisdom teeth could
develop in the lower jaw, from 220 patient records.

Group one, the control group (376 sites), contained x-rays of patients
who had not received anesthesia on the lower jaw where wisdom teeth
could develop. Group two, the comparison group (63 sites), contained
x-rays from patients who had received anesthesia.

In the control group, 1.9% of the sites did not have x-ray evidence of
wisdom tooth buds. In contrast, 7.9% of the sites in the comparison
group – those who had received anesthesia – did not have tooth buds. The
comparison group was 4.35 times more likely to have missing wisdom
tooth buds than the control group.

"The incidence of missing wisdom teeth was significantly higher in the
group that had received dental anesthesia; statistical evidence suggests
that this did not happen by chance alone. We hope our findings
stimulate research using larger sample sizes and longer periods of
observation to confirm our findings and help better understand how
wisdom teeth can be stopped from developing," Silvestri continued.
"Dentists have been giving local anesthesia to children for nearly 100
years and may have been preventing wisdom teeth from forming without
even knowing it. Our findings give hope that a procedure preventing
third molar growth can be developed."

Silvestri has previously published preliminary research on third molar
tooth development, showing that third molars can be stopped from
developing when non- or minimally-invasive techniques are applied to
tooth buds.

About Me

Martin Jablow DMD, is America's Dental Technology Coach. He practices general dentistry in a group setting in Woodbridge, NJ. Dr. Jablow promotes the use of technology in the dental office to improve efficiency and patient care. He lectures and writes articles on the use of technology to enhance the practice of dentistry. Dr. Jablow can be reached by email at marty at dentaltechnologycoach dot com